There are surprisingly active developments in the single-engine helicopter field, with new rotorcraft on the way such as the turbine-powered Robinson R66 and Sikorsky S-434. Kit manufacturer RotorWay is even coming to market with a planned certified turbine helicopter, the 300T Eagle, announced at last year’s EAA AirVenture show. The Russian Helicopters Mi-34S2 Sapsan will also offer turbine power. Eurocopter has no new turbine singles in the pipeline but plans to explore a diesel-powered EC120.
Eurocopter • Bluecopter
Eurocopter is planning to fly an EC120 light single powered by a diesel engine, instead of the usual 504-shp Turbomeca Arrius 2F, next year. The Bluecopter name refers to Eurocopter’s desire to improve the environmental performance of its helicopters.
While the EC120 will be a demonstrator, with an expected 40-percent cut in fuel consumption, it is likely that future Eurocopter light rotorcraft will use this technology. The engines will provide significant advancements in noise and emissions. The main challenge is weight, but Formula 1 technology could provide the materials to make the engine lighter. Eurocopter has rechristened the diesel a “high-compression engine.” The airframer has yet to choose the engine supplier, but Turbomeca is a likely contender.
Russian Helicopters • Mi-34S2
Russian Helicopters is working on a turbine version of the Mi-34 light single, the Mi-34S2 Sapsan, to be powered by a Turbomeca Arrius 2F. The company plans to apply for European and U.S. certification.
The Sapsan (Russian for peregrine falcon) can seat five, including the pilot, and is expected to have a 143-knot max speed, 120-knot cruise speed and 460-nm range. Service ceiling should be 19,600 feet; hover ceilings, in and out of ground effect, will be 12,800 feet and 14,300 feet, respectively. Mtow is slated to be 3,200 pounds.
First delivery is pegged for next year’s fourth quarter, but the company will begin production only if it receives enough orders. It plans to manufacture five Sapsans next year, with a ramp up to 40 per year in 2016.
The $1 million aircraft is aimed at markets such as Russia, CIS countries, Asia, Africa and Latin America. It will enter European Union and U.S. markets beginning in 2016.
Robinson • R66
In 2007 Robinson announced its first turbine helicopter, the Rolls-Royce RR300-powered R66. Three aircraft are currently in flight test and Robinson now anticipates certification in this year’s first half. The company plans to finalize dealer agreements, deposit policies and a price for the R66, believed to be near $1 million, early this year and achieve full-rate production next year. Company founder Frank Robinson thinks that R66 production could eventually reach 150 to 200 annually.
The R66 is bigger than the piston-powered R44 on which it is loosely based. Its luggage bay is large enough for golf clubs. There is one extra seat in back, the pilot seats are wider and legroom is capacious, and the overall cabin is eight inches wider than that of the R44. Empty weight is 1,270 pounds and the useful load comes in at 1,300 pounds, 300 pounds more than an R44. However, due to the RR300’s 23-gph fuel burn, the R66 carries 75 gallons of fuel, while the R44, which burns 15 gph, carries 47 gallons.
Initially, all major R66 components, including the engine, will have a TBO of 2,000 hours, although that is likely to be extended over time to perhaps 2,200 hours. The RR300 weighs about one-third of the Lycoming IO-540 that powers the R44 and produces 225 shp (continuous). Forward speed on the R66 increases slightly to 117 knots and the service ceiling increases to 14,000 feet.
The R66 will have hydro-pneumatic engine controls as opposed to Fadec, and the traditional “six-pack” steam gauges instead of an integrated glass cockpit display. The R66’s main rotor chord is slightly wider than the R44’s, but the diameter is the same. Its fuel system meets new and more stringent crashworthiness standards. The R66 features the same T-bar cyclic as that in the R44 and is designed for easy pilot transition from the R44.
RotorWay • 300T
Kit helicopter company RotorWay launched a new to-be- certified design aimed primarily at the training market in July 2009, but the company’s plan to have a non-conforming prototype ready to fly by early this year appears to have been delayed. RotorWay now hopes to have a helicopter airborne by the middle of this year and certification by the end of next year so customer deliveries can begin in 2012. It should be noted, however, that RotorWay has never before produced an FAA-certified aircraft, suggesting that this timetable might be optimistic. CEO Grant Norwitz said the new helicopter will be priced “less than an R66.” The company is taking $5,000 deposits on the helicopter.
The Eagle will be powered by a Rolls-Royce RR300B1 turbine that is similar–but not identical–to the engine used on the R66. Preliminary specifications for the 2,050-pound two seater include a 1,100-pound useful load, 500-pound external load, 110-knot maximum cruise speed and 13,000-foot ceiling. The Eagle will carry 80 gallons of fuel, for two hours endurance with a 30-minute reserve.
Sikorsky • S-434
The first S-434 flew in December 2008. Sikorsky received an initial order for nine 434s from the Saudi Arabian Ministry of Interior and had delivered two of those helicopters by the end of last year. FAA certification for the 434 is expected later this year.
The 434 is a derivative of the Sikorsky-Schweizer 333 and incorporates several system components developed with Northrop Grumman for the Navy’s MQ-8B Fire Scout vertical takeoff and landing tactical unmanned aerial vehicle. The chief difference between the 333 and the 434 is the latter’s four-blade main rotor, which reduces noise, improves lift and increases mtow and useful load when combined with a more powerful Rolls-Royce 250-C20W engine (320 shp for takeoff). The useful load of the 434 increases by 655 pounds, to 1,855, compared with that of the 333. The 434 also has a larger, 84-gallon fuel tank. This makes the 434 a stronger-performing hot-and-high and utility helicopter suitable for a variety of missions, including training, patrol and sling-load operations. Price is expected to approach $1 million. Sikorsky will continue to produce the 333.